Use turbine parent 12-SNAPSHOT and set commons-pool2 scope provided.
diff --git a/pom.xml b/pom.xml
index 4a4bf4b..4b9a2d3 100644
--- a/pom.xml
+++ b/pom.xml
@@ -19,7 +19,7 @@
   <parent>

     <groupId>org.apache.turbine</groupId>

     <artifactId>turbine-parent</artifactId>

-    <version>11</version>

+    <version>12-SNAPSHOT</version>

     <relativePath></relativePath>

   </parent>

 

@@ -118,10 +118,12 @@
       <artifactId>commons-lang3</artifactId>

       <version>3.9</version>

     </dependency>

+    <!-- scope provided to avoid dependency inconsistencies to commons module dbcp2 -->

     <dependency>

         <groupId>org.apache.commons</groupId>

         <artifactId>commons-pool2</artifactId>

-        <version>2.7.0</version>

+        <version>2.11.1</version>

+        <scope>provided</scope>

     </dependency>

     <!--  fulcrum-pool is required even if not used due to optional fall-back -->

    <dependency>